Friend who obsessively ruminates

I've been friends with this girl for a long time now (10+ years) and she has a rumination problem that she does go to therapy for. However, she will ruminate and flood my phone with paragraphs of her problems via text and it is so exhausting to read and talk about. We are both 25 and in school and I do not have the time or energy to be responding in detail about everything she brings up. Its the same things over and over that she brings up (exes from 4 years ago, friendships with others that ended years ago, insecurities from high school, etc) and I just do not know how to handle it anymore. I feel like a bad friend for feeling this way but I feel like i am a part time therapist at this point. I am a nurse and I do encourage her to talk to her therapist about these things and actively do the therapy techniques that were recommended but its not my place to make her do any of that. I just feel exhausted being her friend right now and I do love and care about her but I also have a lot going on in my life (which she never cares to ask me about) and I just need advice. Just for example, today she sent me 14 texts (paragraphs each) about how weird her ex boyfriend's family was. I just need help with what to do about this.